biological molecules Flashcards
condensation
the removal of a water molecule from the formation of a covalent bond between two biochemical groups
hydrolysis
the breaking down of large molecules into smaller ones by the addition of a molecule of water
Why are inorganic ions important
- cellular processes
- includig muscle contraction and nervous coordinations
what are inorganic ions also known as and describe the amounts they are needed in
- electrolytes
- minute amounts - micronutrients eg zinc
- small amounts - macronutrients
What is the role of magnesium ions
- consitiuent chlorophyll
- therefore needed for photosynthesis
- therfore when lacking leaves appear yellow - chlorosis
What are the roles of iron ions
- constitunet of haemoglobin
- involved in transport of oxygen
- a diet deficients in iron can lead to anaemia
What is the role of calcium ions
- structural component of bones and teeth
- phosphate also required
What is the role of phosphate ions
- needed for making nucleotides including ATP
- a consititudent part of phospholipids in cell membranes
What is an ion
- charged atom or molecule that has gained or lost electrons
dipolar
a polar molecule with a positive and negative charge
hydrogen bond
weak attractive force between a positivley charged hydrogen atom and a negativley charged oxygen or nitrogen atom
Why is water vital to life on earth
- makes up between 65%-95% by mass of most organisms
- allows imprtant reactions to take place
- forms a habitat that covers over 70% of the earth’s surface
Describe water’s basic structure that enables it’s properties to stem from
- dipolar molecule - positivley charged end hydrogen and a negativley charged end oxygen
- no overall charge
- hydrogen bonds easily form between hydrogen on one molecule and oxygen on another
- although individulally there weak collectivley they make it difficult to seperate molecules from each other
Why is water a good solvent and how is this useful for life on earth
- it is involved in many biochemical reactions
- hydrolysis and condenasation
- allows polar molecules eg glucose and ions to dissolve
- acts as a transport medium - eg blood
Why does water have a high specific heat capacity and how is this useful for life on earth
- a large amount of heat energy is needed to increase the temerature of a body of water - due to large numbers of hydrogen bonds that need to be broken
- large fluctuations in temperature are prevented
- aquatic environments are therfore relativley thermally stable
Why does water have a high latent heat of vaporisation and how is this useful for life on earth
- large amounts of heat energy are needed to vaporise water
- often used as a cooling mechanism eg sweating in mammals
Why is water a good metabolite and how is this useful for life on earth
- it is involved in many biochemical reactions
- hydrolysis and condensation
- reactant in photosynthesis
Why does water have cohesion and how is this useful for life on earth
- water molecules attract each other and form hydrogen bonds between themselves
- allows water to be drawn up xylem vessles of trees
- created surface tension allowing insects such as pond skaters to be supported
- also provides support for other aquatic organisms eg jellyfish
Why does water have a high density and how is this useful for life on earth
- water has a maximum density at 4 degrees celcius
- as a result ice floats act as an insulator preventing the water benath from freezing complelteu
- preotecting the aquatic habitat
Why is water transparent and how is this useful for life on earth
- allows light to pass through enabling aquatic plants to photosynthesise
What are carbohydrates
small organic molecules containing carbon, oxygen and hydrogen
What are the role of carbohydrates
- building blocks for more complex molecules eg ribose forms a consituent molecule of RNA
- sources of energy eg glucose
- energy storage molecules eg glycogen and starch
- structural support eg cellulose and chitin
isomer
- molecules with the same chemical formular with a different arrangement of atoms
What are the properties of monosaccharides
- sweet tasting
- soluble in water